The Quadrilateral Security Dialogue (Quad) which groups Australia, India, Japan, and the United States is often being looked at as a potential instrument to check further adventurism of china in Indo-Pacific. Many give the credit of the idea of "Quad countries" to Japanese Prime Minister Shinzo Abe who mooted his proposal within the framework of the "confluence of the two seas," joining the Indian and the Pacific Oceans.
The initial impetus/usefulness of Quad: Quad by nomenclature is a security alliance and not a military alliance; hence the expectations from Quad have to be appropriately restricted for the time being. It appeared to be a military and maritime arrangement revolving exclusively around major democracies - Japan, Australia, India, and the United States.